TPOP-II: Tritium Fueling at a Reactor Scale

As part of the International Thermonuclear Experimental Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabri injection system to test the mechanical and thermal properties of extruded tritium repeating single-stage pneumatic pellet injector, called the Tritium-Proof-of-Principle Phase II (TPOP-II) Pellet Injector, has a piston-driven mechanical extruder and is designed to extrude and accelerate hydrogenic pellets sized for the ITER device. Tritium and D-T pellets have been produced in experiments at the Los Alamos National Laboratory Tritium Systems Test Assembly (TSTA). About 38 g of tritium utilized in the experiment. Two types of runs were made: those in which the material was only extruded and those in which pellets were produced and accelerated with deuterium propellant. These extrusion experiments indicate that both T2 and D-T will require higher extrusion forces than D2 by about a factor of two and that the flow of the material may be characterized by static and dynamic shear strengths. This paper presents results of the TPOP-II extrusion experiments.